Biden vs. Sanders and other things to watch in the first Democratic debates

WASHINGTON – Vermont Senator Bernie Sanders over the past couple of weeks has subtly teed off on former Vice President Joe Biden, criticizing him for his "middle ground" approach on climate change, trade policies and corporate donors.

And Biden hasn't sat idly by. The former vice president has shunned some of Sanders’ key proposals, such as Medicare for all, and routinely pitched his more centrist approach as the more viable option.

While neither has mentioned the other's name, the subtext has been clear. And later this month, the two will come face-to-face for the first time since both announced their respective bids for the Democratic presidential nomination.

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The match-up between Sanders and Biden, who are topping most national polls, is just one of several intriguing storylines to look for as Democrats take the stage in Miami for the two-night event.

The lineup of the 20 candidates who will be in the first debates of the season was announced June 14.

Sen. Cory Booker of New Jersey, Sen. Elizabeth Warren of Massachusetts,

former Rep. Beto O'Rourke of Texas, Sen. Amy Klobuchar of Minnesota, former Rep. John Delaney of Maryland, Rep. Tulsi Gabbard of Hawaii, former Housing Secretary Julián Castro, Rep. Tim Ryan of Ohio, New York City Mayor Bill de Blasio and Gov. Jay Inslee of Washington will be on Wednesday, June 26.

Sanders, Biden, Sen. Kamala Harris of California, South Bend, Indiana, Mayor Pete Buttigieg, Sen. Michael Bennet of Colorado, author Marianne Williamson, Rep. Eric Swalwell of California, Sen. Kirsten Gillibrand of New York, entrepreneur Andrew Yang, and former Colorado Gov. John Hickenlooper of Colorado will be on Thursday, June 27.

The debates offer a chance to define a candidate's campaign — or severely hinder it. Here's what to watch for:

Biden vs. Sanders

One candidate has painted themselves as the standard-bearer of Democratic ideals and the best antidote to a second term by President Donald Trump. The other has proudly called himself a democratic socialist and touted his years of experience fighting for progressive causes. Biden and Sanders will go head-to-head on the second night of the debate to try to prove their vision is the best for the nation.

Biden has led is most national polling, but Sanders has inched closer since Biden joined the race, and this debate could tighten or broaden that polling spread.

Sanders might ding the former Vice President on his stance on Medicare for all (Biden has not endorsed it), his views on climate change (Biden had not endorsed the Green New Deal), and the Vermont Senator's belief that moderate liberalism is not the future of the party.

Biden, on the other hand, has worked to push back against those narratives, praising the passage of Obamacare while he was Vice President and noting his involvement in creating the Trans Pacific Partnership. He has routinely touted his willingness to work across the aisle, and has campaigned heavily in areas where voters previously supported President Barack Obama before supporting Trump in 2016.

“This is a terrific lineup because there will be a real debate over the key set of choices in this Democratic primary,” Sanders’ campaign manager Faiz Shakir said in a news release Friday.

The match-up has shades of 2016 running through it. Hillary Clinton, the eventual Democratic nominee, criticized Sanders then for ideas she thought unattainable and his identity as a democratic socialist. But Sanders' vision has been embraced by swaths of young people and now-popular lawmakers, like Alexandria Ocasio-Cortez. Sanders has repeatedly made the point that he believes Democrats are moving away from from centrist ideas.

A chance to standout on night one

The first leg of the two-night event will not feature the two front-runners, but instead will be a chance for voters to get to know what may be some of their second and third choice candidates.

Warren is the only candidate on the first night debate that has broken double digits in several national polls. She also routinely ranks in the top three in state polling. And in a recent Des Moines Register/CNN/Mediacom Iowa Poll, 14% of respondents chose Warren as their second choice and 32% as their third choice,

Two others on the stage that evening also saw high marks as second and third choices. Booker was 36% of voters third choice in the poll, while O'Rourke was the third choice for 33% of respondents.

Candidates on the first night will have the chance to define their campaigns and introduce themselves to the nation without having to pit themselves specifically against Sanders or Biden.

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Outsider candidates mixed in with heavy-hitters

Yang and Williamson, the only two candidates who have never held public office, will be on the national stage with several senators and a former vice president.

While neither are strangers to bright lights — Williamson is friends with Oprah, after all — but a presidential debate isn't a walk in the park. And several people on stage with them will have participated in some form of political debate before.

But debates often create memorable moments, and that could be a good thing for candidates looking to grow their national profile. Both Yang and Williamson clearly have a base of support, as they were able to meet the DNC's debate criteria around polling and donations. Now they'll be looking to standout in the crowd.

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The young and the older

The two youngest candidates, Buttigieg and Swalwell, will be on stage with the two oldest, Biden and Sanders.

When Buttigieg first announced his campaign, he noted that he is a part of a different generation than many of his Democratic rivals. At 37 years old, Buttigieg is a millennial and doesn't shy away from a label that is often used as a snide put-down.

"It is time to walk away from the politics of the past and toward something totally different," he said during his campaign announcement

Swalwell, 38, is also on the stage on the second night. The four-term California congressman has claimed there needs to be a new generation of leaders who are "willing to go big" to run the country.

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Biden and Sanders, on the the end of the spectrum, are both in their 70s and have combined for more than six decades of holding federal elected office.

The only other candidate under the age of 40, Rep. Seth Moulton, D-Mass., did not qualify for the debate stage.

This article originally appeared on USA TODAY: Biden vs. Sanders and other things to watch in the first Democratic debates